/*
 * Copyright (c) 2023 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

declare function AssertType(value: any, type: string): void;

class A {
    foo():B {
        let v = new B();
        AssertType(v, "B");
        return v;
    }
}

class B extends A {}

let a = new A();
let b = a.foo();
let c = new B();
let d = c.foo();

AssertType(a, "A");
AssertType(b, "B");
AssertType(c, "B");
AssertType(d, "B");
